<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<h2>文件上传</h2>
<form action="/files/upload" method="post" enctype="multipart/form-data">
    <input type="text" name="dir" value="avatar" hidden>
    <input type="file" name="file" accept="image/png,image/jpg">
    <input type="submit" value="点我上传">
</form>
</body>
</html>